/***************************************************************************
 *   fheroes2: https://github.com/ihhub/fheroes2                           *
 *   Copyright (C) 2019 - 2025                                             *
 *                                                                         *
 *   Free Heroes2 Engine: http://sourceforge.net/projects/fheroes2         *
 *   Copyright (C) 2009 by Andrey Afletdinov <fheroes2@gmail.com>          *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the                         *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include "world.h"

#include <algorithm>
#include <array>
#include <cassert>
#include <limits>
#include <optional>
#include <ostream>
#include <set>
#include <tuple>

#include "ai_planner.h"
#include "artifact.h"
#include "campaign_savedata.h"
#include "campaign_scenariodata.h"
#include "castle.h"
#include "color.h"
#include "direction.h"
#include "game.h"
#include "game_io.h"
#include "game_over.h"
#include "ground.h"
#include "heroes.h"
#include "logging.h"
#include "maps_fileinfo.h"
#include "maps_objects.h"
#include "maps_tiles.h"
#include "maps_tiles_helper.h"
#include "mp2.h"
#include "pairs.h"
#include "players.h"
#include "race.h"
#include "rand.h"
#include "resource.h"
#include "route.h"
#include "save_format_version.h"
#include "serialize.h"
#include "settings.h"
#include "tools.h"
#include "translations.h"
#include "ui_font.h"
#include "week.h"
#include "world_object_uid.h"

namespace
{
    bool isTileBlockedForSettingMonster( const int32_t tileId, const int32_t radius, const std::set<int32_t> & excludeTiles )
    {
        const MapsIndexes & indexes = Maps::getAroundIndexes( tileId, radius );

        return std::any_of( indexes.cbegin(), indexes.cend(), [&excludeTiles]( const int32_t indexId ) { return excludeTiles.count( indexId ) > 0; } );
    }

    int32_t findSuitableNeighbouringTile( const std::vector<Maps::Tile> & mapTiles, const int32_t tileId, const bool allDirections, Rand::PCG32 & gen )
    {
        std::vector<int32_t> suitableIds;

        const MapsIndexes & indexes = Maps::getAroundIndexes( tileId );

        for ( const int32_t indexId : indexes ) {
            // If allDirections is false, we should only consider tiles below the current object
            if ( !allDirections && indexId < tileId + world.w() - 2 ) {
                continue;
            }

            const Maps::Tile & indexedTile = mapTiles[indexId];

            if ( indexedTile.isWater() || !isClearGround( indexedTile ) ) {
                continue;
            }

            const MP2::MapObjectType objectType = indexedTile.getMainObjectType( true );

            // TODO: Check if the original game can spawn a monster over an event and if so whether the event keeps working after the monster is killed.
            if ( objectType == MP2::OBJ_EVENT ) {
                // The event is not considered as in-game action object to avoid confusion with visible action objects.
                // We skip the tile with an event because there cannot be two action objects (monster and event) on one tile.
                // And we don't need to leave space between event and spawned monster so we don't add tile to `excludeTiles`.

                continue;
            }

            // If the candidate tile is a coast tile, it is suitable only if there are other coast tiles nearby
            if ( objectType == MP2::OBJ_COAST ) {
                const MapsIndexes coastTiles = Maps::ScanAroundObject( indexId, MP2::OBJ_COAST );

                if ( coastTiles.empty() ) {
                    continue;
                }
            }

            suitableIds.emplace_back( indexId );
        }

        if ( suitableIds.empty() ) {
            return -1;
        }

        return Rand::GetWithGen( suitableIds, gen );
    }

    int32_t getNeighbouringEmptyTileCount( const std::vector<Maps::Tile> & mapTiles, const int32_t tileId )
    {
        int32_t count = 0;

        const MapsIndexes & indexes = Maps::getAroundIndexes( tileId );

        for ( const int32_t indexId : indexes ) {
            const Maps::Tile & indexedTile = mapTiles[indexId];
            if ( indexedTile.isWater() || !isClearGround( indexedTile ) ) {
                continue;
            }

            ++count;
        }

        return count;
    }
}

MapBaseObject * MapObjects::get( const uint32_t uid ) const
{
    if ( const auto iter = _objects.find( uid ); iter != _objects.end() ) {
        return iter->second.get();
    }

    return nullptr;
}

std::list<MapBaseObject *> MapObjects::get( const fheroes2::Point & pos ) const
{
    std::list<MapBaseObject *> result;

    for ( const auto & [dummy, obj] : _objects ) {
        assert( obj );

        if ( !obj->isPosition( pos ) ) {
            continue;
        }

        result.push_back( obj.get() );
    }

    return result;
}

void CapturedObjects::SetColor( const int32_t index, const PlayerColor color )
{
    Get( index ).SetColor( color );
}

void CapturedObjects::Set( const int32_t index, const MP2::MapObjectType obj, const PlayerColor color )
{
    CapturedObject & capturedObj = Get( index );

    if ( capturedObj.GetColor() != color && capturedObj.guardians.isValid() ) {
        capturedObj.guardians.Reset();
    }

    capturedObj.Set( obj, color );
}

uint32_t CapturedObjects::GetCount( const MP2::MapObjectType objectType, const PlayerColor ownerColor ) const
{
    uint32_t result = 0;

    const ObjectColor objCol( objectType, ownerColor );

    for ( const auto & [idx, capturedObj] : *this ) {
        if ( capturedObj.objCol != objCol ) {
            continue;
        }

        ++result;
    }

    return result;
}

uint32_t CapturedObjects::GetCountMines( const int resourceType, const PlayerColor ownerColor ) const
{
    uint32_t count = 0;

    const ObjectColor objCol( MP2::OBJ_MINE, ownerColor );

    for ( const auto & [idx, capturedObj] : *this ) {
        if ( capturedObj.objCol != objCol ) {
            continue;
        }

        if ( resourceType != Maps::getDailyIncomeObjectResources( world.getTile( idx ) ).getFirstValidResource().first ) {
            continue;
        }

        ++count;
    }

    return count;
}

PlayerColor CapturedObjects::GetColor( const int32_t index ) const
{
    const auto iter = find( index );
    if ( iter == end() ) {
        return PlayerColor::NONE;
    }

    return iter->second.GetColor();
}

void CapturedObjects::ClearFog( const PlayerColorsSet colors ) const
{
    for ( const auto & [idx, capturedObj] : *this ) {
        const auto [objectType, objectColor] = capturedObj.objCol;

        if ( !( colors & objectColor ) ) {
            continue;
        }

        int32_t scoutingDistance = 0;

        switch ( objectType ) {
        case MP2::OBJ_MINE:
        case MP2::OBJ_ALCHEMIST_LAB:
        case MP2::OBJ_SAWMILL:
        case MP2::OBJ_LIGHTHOUSE:
            scoutingDistance = 3;
            break;

        default:
            break;
        }

        if ( scoutingDistance == 0 ) {
            continue;
        }

        Maps::ClearFog( idx, scoutingDistance, objectColor );
    }
}

void CapturedObjects::ResetColor( const PlayerColor color )
{
    for ( auto & [tileIndex, capturedObj] : *this ) {
        auto & [objectType, objectColor] = capturedObj.objCol;

        if ( objectColor != color ) {
            continue;
        }

        objectColor = PlayerColor::NONE;
        world.getTile( tileIndex ).setOwnershipFlag( objectType, objectColor );
    }
}

World & world = World::Get();

World & World::Get()
{
    static World insideWorld;

    return insideWorld;
}

void World::Defaults()
{
    // playing kingdom
    vec_kingdoms.Init();

    // Map seed is random and persisted on saves
    // this has to be generated before initializing heroes, as campaign-specific heroes start at a higher level and thus have to simulate level ups
    _seed = Rand::Get( std::numeric_limits<uint32_t>::max() );

    // initialize all heroes
    vec_heroes.Init();

    vec_castles.Init();
}

void World::Reset()
{
    width = 0;
    height = 0;

    // maps tiles
    vec_tiles.clear();

    // kingdoms
    vec_kingdoms.clear();

    // event day
    vec_eventsday.clear();

    // rumors
    _customRumors.clear();

    // castles
    vec_castles.Clear();

    // heroes
    vec_heroes.Clear();

    // extra
    map_captureobj.clear();
    map_objects.clear();

    ultimate_artifact.Reset();

    day = 0;
    week = 0;
    month = 0;

    heroIdAsWinCondition = Heroes::UNKNOWN;
    heroIdAsLossCondition = Heroes::UNKNOWN;

    _seed = 0;
}

void World::generateBattleOnlyMap()
{
    const std::vector<int> terrainTypes{ Maps::Ground::DESERT, Maps::Ground::SNOW, Maps::Ground::SWAMP, Maps::Ground::WASTELAND, Maps::Ground::BEACH,
                                         Maps::Ground::LAVA,   Maps::Ground::DIRT, Maps::Ground::GRASS, Maps::Ground::WATER };

    generateUninitializedMap( 2 );

    const int groundType = Rand::Get( terrainTypes );

    for ( size_t i = 0; i < vec_tiles.size(); ++i ) {
        vec_tiles[i].setIndex( static_cast<int32_t>( i ) );
        vec_tiles[i].setTerrain( Maps::Ground::getTerrainStartImageIndex( groundType ), 0 );
    }
}

void World::generateUninitializedMap( const int32_t size )
{
    assert( size > 0 );

    Reset();

    width = size;
    height = size;

    Maps::FileInfo fi;

    fi.width = static_cast<uint16_t>( width );
    fi.height = static_cast<uint16_t>( height );

    Settings & conf = Settings::Get();

    if ( conf.isPriceOfLoyaltySupported() ) {
        fi.version = GameVersion::PRICE_OF_LOYALTY;
    }

    conf.setCurrentMapInfo( std::move( fi ) );

    Defaults();

    // The tiles are cleared and resizing their vector also initializes tiles with the default values.
    assert( vec_tiles.empty() );
    vec_tiles.resize( static_cast<size_t>( width ) * height );
}

const Castle * World::getCastleEntrance( const fheroes2::Point & tilePosition ) const
{
    if ( !isValidCastleEntrance( tilePosition ) ) {
        return nullptr;
    }

    return vec_castles.Get( tilePosition );
}

Castle * World::getCastleEntrance( const fheroes2::Point & tilePosition )
{
    if ( !isValidCastleEntrance( tilePosition ) ) {
        return nullptr;
    }

    return vec_castles.Get( tilePosition );
}

bool World::isValidCastleEntrance( const fheroes2::Point & tilePosition ) const
{
    return Maps::isValidAbsPoint( tilePosition.x, tilePosition.y ) && ( getTile( tilePosition.x, tilePosition.y ).getMainObjectType( false ) == MP2::OBJ_CASTLE );
}

Heroes * World::GetHeroForHire( const int race, const int heroIDToIgnore /* = Heroes::UNKNOWN */ ) const
{
    return vec_heroes.GetHeroForHire( race, heroIDToIgnore );
}

Heroes * World::FromJailHeroes( const int32_t tileIndex )
{
    return vec_heroes.FromJail( tileIndex );
}

Heroes * World::GetHero( const Castle & castle ) const
{
    return vec_heroes.Get( castle.GetCenter() );
}

int World::GetDay() const
{
    return LastDay() ? numOfDaysPerWeek : day % numOfDaysPerWeek;
}

int World::GetWeek() const
{
    return LastWeek() ? numOfWeeksPerMonth : week % numOfWeeksPerMonth;
}

bool World::BeginWeek() const
{
    return 1 == ( day % numOfDaysPerWeek );
}

bool World::BeginMonth() const
{
    return 1 == ( week % numOfWeeksPerMonth ) && BeginWeek();
}

bool World::LastDay() const
{
    return ( 0 == ( day % numOfDaysPerWeek ) );
}

bool World::FirstWeek() const
{
    return ( 1 == ( week % numOfWeeksPerMonth ) );
}

bool World::LastWeek() const
{
    return ( 0 == ( week % numOfWeeksPerMonth ) );
}

const Week & World::GetWeekType() const
{
    static auto cachedWeekDependencies = std::make_tuple( week, GetWeekSeed() );
    static Week cachedWeek = Week::RandomWeek( FirstWeek(), GetWeekSeed() );

    const auto currentWeekDependencies = std::make_tuple( week, GetWeekSeed() );

    if ( cachedWeekDependencies != currentWeekDependencies ) {
        cachedWeekDependencies = currentWeekDependencies;
        cachedWeek = Week::RandomWeek( FirstWeek(), GetWeekSeed() );
    }

    return cachedWeek;
}

void World::NewDay()
{
    ++day;

    if ( BeginWeek() ) {
        ++week;

        if ( BeginMonth() ) {
            ++month;
        }
    }

    // first the routine of the new month
    if ( BeginMonth() ) {
        NewMonth();
    }

    // then the routine of the new week
    if ( BeginWeek() ) {
        NewWeek();

        vec_kingdoms.NewWeek();
        vec_castles.NewWeek();
        vec_heroes.NewWeek();
    }

    // and finally the routine of the new day
    vec_kingdoms.NewDay();
    vec_castles.NewDay();
    vec_heroes.NewDay();

    // remove deprecated events
    assert( day > 0 );

    vec_eventsday.remove_if( [this]( const EventDate & v ) { return v.isDeprecated( day - 1 ); } );
}

void World::NewWeek()
{
    // update objects
    if ( week > 1 ) {
        for ( Maps::Tile & tile : vec_tiles ) {
            if ( MP2::isWeekLife( tile.getMainObjectType( false ) ) || tile.getMainObjectType() == MP2::OBJ_MONSTER ) {
                updateObjectInfoTile( tile, false );
            }
        }
    }

    // Reset RECRUIT mode for all heroes at once
    vec_heroes.ResetModes( Heroes::RECRUIT );

    // Reset recruits in all kingdoms at once
    std::set<Heroes *> remainingRecruits = vec_kingdoms.resetRecruits();

    // Restore the RECRUIT mode for the remaining recruits
    for ( Heroes * hero : remainingRecruits ) {
        assert( hero != nullptr );

        hero->SetModes( Heroes::RECRUIT );
    }
}

void World::NewMonth()
{
    if ( month > 1 && GetWeekType().GetType() == WeekName::MONSTERS ) {
        _monthOfMonstersAction( Monster( GetWeekType().GetMonster() ) );
    }
}

void World::_monthOfMonstersAction( const Monster & mons )
{
    if ( !mons.isValid() ) {
        return;
    }

    // Find all tiles which are useful for monsters such as resources, artifacts, mines, other capture objects. Exclude heroes, monsters and castles.
    std::vector<int32_t> primaryTargetTiles;

    // Sometimes monsters appear on roads so find all road tiles.
    std::vector<int32_t> secondaryTargetTiles;

    // Lastly monster occasionally appear on empty tiles.
    std::vector<int32_t> tetriaryTargetTiles;

    std::set<int32_t> excludeTiles;

    Rand::PCG32 seededGen( _seed + month );

    // First we scan for Heroes, Castles and Monsters to exclude these from tiles and nearby tiles.
    // We must do this prior to checking the possibility for a monster to spawn in order to properly perform the check on nearby tiles.
    std::for_each( vec_tiles.cbegin(), vec_tiles.cend(), [&excludeTiles]( const Maps::Tile & tile ) {
        const MP2::MapObjectType objectType = tile.getMainObjectType( true );
        if ( objectType == MP2::OBJ_CASTLE || objectType == MP2::OBJ_HERO || objectType == MP2::OBJ_MONSTER ) {
            excludeTiles.emplace( tile.GetIndex() );
        }
    } );

    for ( const Maps::Tile & tile : vec_tiles ) {
        if ( tile.isWater() ) {
            // Monsters are not placed on water.
            continue;
        }

        const int32_t tileId = tile.GetIndex();

        if ( excludeTiles.count( tileId ) > 0 ) {
            continue;
        }

        const MP2::MapObjectType objectType = tile.getMainObjectType( true );

        if ( MP2::isInGameActionObject( objectType ) ) {
            if ( isTileBlockedForSettingMonster( tileId, 3, excludeTiles ) ) {
                continue;
            }

            const int32_t tileToSet = findSuitableNeighbouringTile( vec_tiles, tileId, ( tile.GetPassable() == DIRECTION_ALL ), seededGen );
            if ( tileToSet >= 0 ) {
                primaryTargetTiles.emplace_back( tileToSet );
                excludeTiles.emplace( tileId );
            }
        }
        else if ( tile.isRoad() ) {
            if ( isTileBlockedForSettingMonster( tileId, 4, excludeTiles ) ) {
                continue;
            }

            if ( getNeighbouringEmptyTileCount( vec_tiles, tileId ) < 2 ) {
                continue;
            }

            const int32_t tileToSet = findSuitableNeighbouringTile( vec_tiles, tileId, true, seededGen );
            if ( tileToSet >= 0 ) {
                secondaryTargetTiles.emplace_back( tileToSet );
                excludeTiles.emplace( tileId );
            }
        }
        else if ( isClearGround( tile ) ) {
            if ( isTileBlockedForSettingMonster( tileId, 4, excludeTiles ) ) {
                continue;
            }

            if ( getNeighbouringEmptyTileCount( vec_tiles, tileId ) < 4 ) {
                continue;
            }

            const int32_t tileToSet = findSuitableNeighbouringTile( vec_tiles, tileId, true, seededGen );
            if ( tileToSet >= 0 ) {
                tetriaryTargetTiles.emplace_back( tileToSet );
                excludeTiles.emplace( tileId );
            }
        }
    }

    // Shuffle all found tile IDs.
    Rand::ShuffleWithGen( primaryTargetTiles, seededGen );
    Rand::ShuffleWithGen( secondaryTargetTiles, seededGen );
    Rand::ShuffleWithGen( tetriaryTargetTiles, seededGen );

    // Calculate the number of monsters to be placed.
    uint32_t monstersToBePlaced = static_cast<uint32_t>( primaryTargetTiles.size() / 3 );
    const uint32_t mapMinimum = static_cast<uint32_t>( vec_tiles.size() / 360 );

    if ( monstersToBePlaced < mapMinimum ) {
        monstersToBePlaced = mapMinimum;
    }
    else {
        monstersToBePlaced = Rand::GetWithGen( monstersToBePlaced * 75 / 100, monstersToBePlaced * 125 / 100, seededGen );
    }

    // 85% of positions are for primary targets
    // 10% of positions are for roads
    // 5% of positions are for empty tiles
    uint32_t primaryTileCount = monstersToBePlaced * 85 / 100;
    if ( primaryTileCount > primaryTargetTiles.size() ) {
        primaryTileCount = static_cast<uint32_t>( primaryTargetTiles.size() );
    }

    for ( uint32_t i = 0; i < primaryTileCount; ++i ) {
        setMonsterOnTile( vec_tiles[primaryTargetTiles[i]], mons, 0 /* random */ );
    }

    uint32_t secondaryTileCount = monstersToBePlaced * 10 / 100;
    if ( secondaryTileCount > secondaryTargetTiles.size() ) {
        secondaryTileCount = static_cast<uint32_t>( secondaryTargetTiles.size() );
    }

    for ( uint32_t i = 0; i < secondaryTileCount; ++i ) {
        setMonsterOnTile( vec_tiles[secondaryTargetTiles[i]], mons, 0 /* random */ );
    }

    uint32_t tetriaryTileCount = monstersToBePlaced * 5 / 100;
    if ( tetriaryTileCount > tetriaryTargetTiles.size() ) {
        tetriaryTileCount = static_cast<uint32_t>( tetriaryTargetTiles.size() );
    }

    for ( uint32_t i = 0; i < tetriaryTileCount; ++i ) {
        setMonsterOnTile( vec_tiles[tetriaryTargetTiles[i]], mons, 0 /* random */ );
    }
}

fheroes2::LocalizedString World::getCurrentRumor() const
{
    const uint32_t standardRumorCount = 9;
    const uint32_t totalRumorCount = static_cast<uint32_t>( _customRumors.size() ) + standardRumorCount;
    const uint32_t chosenRumorId = Rand::GetWithSeed( 0, totalRumorCount - 1, GetWeekSeed() );

    switch ( chosenRumorId ) {
    case 0: {
        std::string rumor( _( "The ultimate artifact is really the %{name}." ) );
        StringReplace( rumor, "%{name}", ultimate_artifact.GetName() );
        return { rumor, std::nullopt };
    }
    case 1: {
        std::string rumor( _( "The ultimate artifact may be found in the %{name} regions of the world." ) );
        const int32_t artifactIndex = ultimate_artifact.getPosition();
        const fheroes2::Point artifactPos = Maps::GetPoint( artifactIndex );

        if ( height / 3 > artifactPos.y ) {
            if ( width / 3 > artifactPos.x ) {
                StringReplace( rumor, "%{name}", _( "north-west" ) );
            }
            else if ( 2 * width / 3 > artifactPos.x ) {
                StringReplace( rumor, "%{name}", _( "north" ) );
            }
            else {
                StringReplace( rumor, "%{name}", _( "north-east" ) );
            }
        }
        else if ( 2 * height / 3 > artifactPos.y ) {
            if ( width / 3 > artifactPos.x ) {
                StringReplace( rumor, "%{name}", _( "west" ) );
            }
            else if ( 2 * width / 3 > artifactPos.x ) {
                StringReplace( rumor, "%{name}", _( "center" ) );
            }
            else {
                StringReplace( rumor, "%{name}", _( "east" ) );
            }
        }
        else if ( width / 3 > artifactPos.x ) {
            StringReplace( rumor, "%{name}", _( "south-west" ) );
        }
        else if ( 2 * width / 3 > artifactPos.x ) {
            StringReplace( rumor, "%{name}", _( "south" ) );
        }
        else {
            StringReplace( rumor, "%{name}", _( "south-east" ) );
        }
        return { rumor, std::nullopt };
    }
    case 2:
        return { _( "The truth is out there." ), std::nullopt };
    case 3:
        return { _( "The dark side is stronger." ), std::nullopt };
    case 4:
        return { _( "The end of the world is near." ), std::nullopt };
    case 5:
        return { _( "The bones of Lord Slayer are buried in the foundation of the arena." ), std::nullopt };
    case 6:
        return { _( "A Black Dragon will take out a Titan any day of the week." ), std::nullopt };
    case 7:
        return { _( "He told her: Yada yada yada... and then she said: Blah, blah, blah..." ), std::nullopt };
    case 8:
        return { _( "An unknown force is being resurrected..." ), std::nullopt };
    default:
        break;
    }

    assert( chosenRumorId >= standardRumorCount && chosenRumorId < totalRumorCount );
    return { _customRumors[chosenRumorId - standardRumorCount], Settings::Get().getCurrentMapInfo().getSupportedLanguage() };
}

MapsIndexes World::GetTeleportEndPoints( const int32_t index ) const
{
    MapsIndexes result;

    const Maps::Tile & entranceTile = getTile( index );

    if ( entranceTile.getMainObjectType( false ) != MP2::OBJ_STONE_LITHS ) {
        return result;
    }

    const Maps::ObjectPart * entranceObjectPart = Maps::getObjectPartByActionType( entranceTile, MP2::OBJ_STONE_LITHS );
    if ( entranceObjectPart == nullptr ) {
        // This tile is marked as Stone Liths but somehow it doesn't even have Stone Liths' object parts.
        assert( 0 );
        return result;
    }

    // The type of destination stone liths must match the type of the source stone liths.
    for ( const int32_t teleportIndex : _allTeleports.at( entranceObjectPart->icnIndex ) ) {
        const Maps::Tile & teleportTile = getTile( teleportIndex );

        if ( teleportIndex == index || teleportTile.getMainObjectType() != MP2::OBJ_STONE_LITHS || teleportTile.isWater() != entranceTile.isWater() ) {
            continue;
        }

        assert( teleportTile.getHero() == nullptr );

        result.push_back( teleportIndex );
    }

    return result;
}

int32_t World::NextTeleport( const int32_t index ) const
{
    const MapsIndexes teleports = GetTeleportEndPoints( index );
    if ( teleports.empty() ) {
        DEBUG_LOG( DBG_GAME, DBG_WARN, "not found" )
        return index;
    }

    return Rand::Get( teleports );
}

MapsIndexes World::GetWhirlpoolEndPoints( const int32_t index ) const
{
    MapsIndexes result;

    const Maps::Tile & entranceTile = getTile( index );

    if ( entranceTile.getMainObjectType( false ) != MP2::OBJ_WHIRLPOOL ) {
        return result;
    }

    const Maps::ObjectPart * entranceObjectPart = Maps::getObjectPartByActionType( entranceTile, MP2::OBJ_WHIRLPOOL );
    if ( entranceObjectPart == nullptr ) {
        // This tile is marked as Whirlpool but somehow it doesn't even have whirlpool's object parts.
        assert( 0 );
        return result;
    }

    for ( const int32_t whirlpoolIndex : _allWhirlpools.at( entranceObjectPart->icnIndex ) ) {
        const Maps::Tile & whirlpoolTile = getTile( whirlpoolIndex );
        if ( whirlpoolTile.getMainObjectType() != MP2::OBJ_WHIRLPOOL ) {
            continue;
        }

        const Maps::ObjectPart * destinationObjectPart = Maps::getObjectPartByActionType( whirlpoolTile, MP2::OBJ_WHIRLPOOL );
        if ( destinationObjectPart == nullptr ) {
            // This tile is marked as Whirlpool but somehow it doesn't even have whirlpool's object parts.
            assert( 0 );
            continue;
        }

        if ( destinationObjectPart->_uid == entranceObjectPart->_uid ) {
            continue;
        }

        assert( whirlpoolTile.getHero() == nullptr );

        result.push_back( whirlpoolIndex );
    }

    return result;
}

int32_t World::NextWhirlpool( const int32_t index ) const
{
    const MapsIndexes whilrpools = GetWhirlpoolEndPoints( index );
    if ( whilrpools.empty() ) {
        DEBUG_LOG( DBG_GAME, DBG_WARN, "not found" )
        return index;
    }

    return Rand::Get( whilrpools );
}

uint32_t World::CountCapturedObject( const MP2::MapObjectType obj, const PlayerColor color ) const
{
    return map_captureobj.GetCount( obj, color );
}

uint32_t World::CountCapturedMines( const int type, const PlayerColor color ) const
{
    switch ( type ) {
    case Resource::WOOD:
        return CountCapturedObject( MP2::OBJ_SAWMILL, color );
    case Resource::MERCURY:
        return CountCapturedObject( MP2::OBJ_ALCHEMIST_LAB, color );
    default:
        break;
    }

    return map_captureobj.GetCountMines( type, color );
}

void World::CaptureObject( const int32_t index, const PlayerColor color )
{
    assert( Color::Count( static_cast<PlayerColorsSet>( color ) ) <= 1 );

    const MP2::MapObjectType objectType = getTile( index ).getMainObjectType( false );

    // The owner can be set not only for the objects returned by `MP2::isCaptureObject()`.
    // In example, dwellings can also marked by the player's color.
    map_captureobj.Set( index, objectType, color );

    if ( color != PlayerColor::NONE && !( Color::allPlayerColors() & color ) ) {
        return;
    }

    Castle * castle = getCastleEntrance( Maps::GetPoint( index ) );
    if ( castle && castle->GetColor() != color ) {
        castle->ChangeColor( color );
    }

    getTile( index ).setOwnershipFlag( objectType, color );
}

PlayerColor World::ColorCapturedObject( const int32_t index ) const
{
    return map_captureobj.GetColor( index );
}

CapturedObject & World::GetCapturedObject( const int32_t index )
{
    return map_captureobj.Get( index );
}

void World::ResetCapturedObjects( const PlayerColor color )
{
    map_captureobj.ResetColor( color );
}

void World::ClearFog( PlayerColor color ) const
{
    const PlayerColorsSet colors = Players::GetPlayerFriends( color );

    // clear abroad castles
    vec_castles.Scout( colors );

    // clear abroad heroes
    vec_heroes.Scout( colors );

    map_captureobj.ClearFog( colors );
}

const UltimateArtifact & World::GetUltimateArtifact() const
{
    return ultimate_artifact;
}

bool World::DiggingForUltimateArtifact( const fheroes2::Point & center )
{
    Maps::Tile & tile = getTile( center.x, center.y );

    // Get digging hole sprite.
    MP2::ObjectIcnType objectIcnType = MP2::OBJ_ICN_TYPE_UNKNOWN;
    uint8_t imageIndex = 0;

    if ( !MP2::getDiggingHoleSprite( tile.GetGround(), objectIcnType, imageIndex ) ) {
        // Are you sure that you can dig here?
        assert( 0 );

        return false;
    }

    tile.pushGroundObjectPart( Maps::ObjectPart( Maps::BACKGROUND_LAYER, Maps::getNewObjectUID(), objectIcnType, imageIndex ) );

    if ( ultimate_artifact.isPosition( tile.GetIndex() ) && !ultimate_artifact.isFound() ) {
        ultimate_artifact.markAsFound();
        return true;
    }

    return false;
}

void World::AddEventDate( const EventDate & event )
{
    vec_eventsday.push_back( event );
}

EventsDate World::GetEventsDate( const PlayerColor color ) const
{
    EventsDate res;

    for ( const EventDate & event : vec_eventsday ) {
        if ( event.isAllow( color, day ) ) {
            res.push_back( event );
        }
    }

    return res;
}

std::string World::DateString() const
{
    std::string output( "month: " );
    output += std::to_string( GetMonth() );
    output += ", week: ";
    output += std::to_string( GetWeek() );
    output += ", day: ";
    output += std::to_string( GetDay() );

    return output;
}

uint32_t World::CountObeliskOnMaps()
{
    const size_t res = std::count_if( vec_tiles.begin(), vec_tiles.end(), []( const Maps::Tile & tile ) { return MP2::OBJ_OBELISK == tile.getMainObjectType( false ); } );
    return res > 0 ? static_cast<uint32_t>( res ) : 6;
}

void World::ActionForMagellanMaps( const PlayerColor color )
{
    const Kingdom & kingdom = world.GetKingdom( color );
    const bool isAIPlayer = kingdom.isControlAI();

    const PlayerColorsSet alliedColors = Players::GetPlayerFriends( color );

    for ( Maps::Tile & tile : vec_tiles ) {
        if ( tile.isWater() ) {
            if ( isAIPlayer && tile.isFog( color ) ) {
                AI::Planner::Get().revealFog( tile, kingdom );
            }

            tile.ClearFog( alliedColors );
        }
    }
}

MapEvent * World::GetMapEvent( const fheroes2::Point & pos )
{
    std::list<MapBaseObject *> res = map_objects.get( pos );
    if ( res.empty() ) {
        return nullptr;
    }

    return dynamic_cast<MapEvent *>( res.front() );
}

MapBaseObject * World::GetMapObject( uint32_t uid )
{
    return uid ? map_objects.get( uid ) : nullptr;
}

void World::RemoveMapObject( const MapBaseObject * obj )
{
    if ( obj ) {
        map_objects.remove( obj->GetUID() );
    }
}

const Heroes * World::GetHeroesCondWins() const
{
    return ( ( Settings::Get().getCurrentMapInfo().ConditionWins() & GameOver::WINS_HERO ) != 0 ) ? GetHeroes( heroIdAsWinCondition ) : nullptr;
}

const Heroes * World::GetHeroesCondLoss() const
{
    return ( ( Settings::Get().getCurrentMapInfo().ConditionLoss() & GameOver::LOSS_HERO ) != 0 ) ? GetHeroes( heroIdAsLossCondition ) : nullptr;
}

bool World::KingdomIsWins( const Kingdom & kingdom, const uint32_t wins ) const
{
#ifndef NDEBUG
#if defined( WITH_DEBUG )
    const Player * kingdomPlayer = Players::Get( kingdom.GetColor() );
    assert( kingdomPlayer != nullptr );

    const bool isKingdomInAIAutoControlMode = kingdomPlayer->isAIAutoControlMode();
#else
    const bool isKingdomInAIAutoControlMode = false;
#endif // WITH_DEBUG
#endif // !NDEBUG

    const Maps::FileInfo & mapInfo = Settings::Get().getCurrentMapInfo();

    switch ( wins ) {
    case GameOver::WINS_ALL:
        // This method should be called with this condition only for a human-controlled kingdom
        assert( kingdom.isControlHuman() || isKingdomInAIAutoControlMode );

        return static_cast<PlayerColorsSet>( kingdom.GetColor() ) == vec_kingdoms.GetNotLossColors();

    case GameOver::WINS_TOWN: {
        const Castle * town = getCastleEntrance( mapInfo.WinsMapsPositionObject() );
        return ( kingdom.isControlHuman() || mapInfo.WinsCompAlsoWins() ) && ( town && town->GetColor() == kingdom.GetColor() );
    }

    case GameOver::WINS_HERO: {
        // This method should be called with this condition only for a human-controlled kingdom
        assert( kingdom.isControlHuman() || isKingdomInAIAutoControlMode );

        if ( heroIdAsWinCondition == Heroes::UNKNOWN ) {
            return false;
        }

        const Heroes * hero = GetHeroesCondWins();
        assert( hero != nullptr );

        // The hero in question should either be available for hire or be hired by a human-controlled kingdom
        return ( hero->isAvailableForHire() || GetKingdom( hero->GetColor() ).isControlHuman() );
    }

    case GameOver::WINS_ARTIFACT: {
        const VecHeroes & heroes = kingdom.GetHeroes();
        if ( mapInfo.WinsFindUltimateArtifact() ) {
            return std::any_of( heroes.begin(), heroes.end(), []( const Heroes * hero ) { return hero->HasUltimateArtifact(); } );
        }
        else {
            const Artifact art = mapInfo.WinsFindArtifactID();
            return std::any_of( heroes.begin(), heroes.end(), [&art]( const Heroes * hero ) { return hero->hasArtifact( art ); } );
        }
    }

    case GameOver::WINS_SIDE:
        // This method should be called with this condition only for a human-controlled kingdom
        assert( kingdom.isControlHuman() || isKingdomInAIAutoControlMode );

        return ( Game::GetActualKingdomColors() & ~Players::GetPlayerFriends( kingdom.GetColor() ) ) == 0;

    case GameOver::WINS_GOLD:
        return ( ( kingdom.isControlHuman() || mapInfo.WinsCompAlsoWins() ) && 0 < kingdom.GetFunds().Get( Resource::GOLD )
                 && static_cast<uint32_t>( kingdom.GetFunds().Get( Resource::GOLD ) ) >= mapInfo.getWinningGoldAccumulationValue() );

    default:
        break;
    }

    return false;
}

bool World::KingdomIsLoss( const Kingdom & kingdom, const uint32_t loss ) const
{
#ifndef NDEBUG
#if defined( WITH_DEBUG )
    const Player * kingdomPlayer = Players::Get( kingdom.GetColor() );
    assert( kingdomPlayer != nullptr );

    const bool isKingdomInAIAutoControlMode = kingdomPlayer->isAIAutoControlMode();
#else
    const bool isKingdomInAIAutoControlMode = false;
#endif // WITH_DEBUG
#endif // !NDEBUG

    // This method should only be called for a human-controlled kingdom
    assert( kingdom.isControlHuman() || isKingdomInAIAutoControlMode );

    const Settings & conf = Settings::Get();

    switch ( loss ) {
    case GameOver::LOSS_ALL:
        return kingdom.isLoss();

    case GameOver::LOSS_TOWN: {
        const Castle * town = getCastleEntrance( conf.getCurrentMapInfo().LossMapsPositionObject() );
        return ( town && town->GetColor() != kingdom.GetColor() );
    }

    case GameOver::LOSS_HERO: {
        if ( heroIdAsLossCondition == Heroes::UNKNOWN ) {
            return false;
        }

        const Heroes * hero = GetHeroesCondLoss();
        assert( hero != nullptr );

        // The hero in question should either be available for hire...
        if ( hero->isAvailableForHire() ) {
            return true;
        }

#if defined( WITH_DEBUG )
        const Player * heroPlayer = Players::Get( hero->GetColor() );
        assert( heroPlayer != nullptr );

        const bool isHeroInAIAutoControlMode = heroPlayer->isAIAutoControlMode();
#else
        const bool isHeroInAIAutoControlMode = false;
#endif

        // .. or be hired by an AI-controlled kingdom
        if ( GetKingdom( hero->GetColor() ).isControlAI() && !isHeroInAIAutoControlMode ) {
            // Exception for campaign: hero is not considered lost if he is hired by a friendly AI-controlled kingdom
            if ( conf.isCampaignGameType() && Players::isFriends( kingdom.GetColor(), static_cast<PlayerColorsSet>( hero->GetColor() ) ) ) {
                return false;
            }

            return true;
        }

        return false;
    }

    case GameOver::LOSS_TIME:
        return ( CountDay() > conf.getCurrentMapInfo().LossCountDays() );

    default:
        break;
    }

    return false;
}

uint32_t World::CheckKingdomWins( const Kingdom & kingdom ) const
{
#ifndef NDEBUG
#if defined( WITH_DEBUG )
    const Player * kingdomPlayer = Players::Get( kingdom.GetColor() );
    assert( kingdomPlayer != nullptr );

    const bool isKingdomInAIAutoControlMode = kingdomPlayer->isAIAutoControlMode();
#else
    const bool isKingdomInAIAutoControlMode = false;
#endif // WITH_DEBUG
#endif // !NDEBUG

    // This method should only be called for a human-controlled kingdom
    assert( kingdom.isControlHuman() || isKingdomInAIAutoControlMode );

    const Settings & conf = Settings::Get();

    if ( conf.isCampaignGameType() && Campaign::getCurrentScenarioVictoryCondition() == Campaign::ScenarioVictoryCondition::CAPTURE_DRAGON_CITY ) {
        if ( kingdom.isVisited( MP2::OBJ_DRAGON_CITY ) ) {
            return GameOver::WINS_SIDE;
        }

        return GameOver::COND_NONE;
    }

    const std::array<uint32_t, 6> victoryConditions
        = { GameOver::WINS_ALL, GameOver::WINS_TOWN, GameOver::WINS_HERO, GameOver::WINS_ARTIFACT, GameOver::WINS_SIDE, GameOver::WINS_GOLD };

    for ( const uint32_t cond : victoryConditions ) {
        if ( ( ( conf.getCurrentMapInfo().ConditionWins() & cond ) == cond ) && KingdomIsWins( kingdom, cond ) ) {
            return cond;
        }
    }

    return GameOver::COND_NONE;
}

uint32_t World::CheckKingdomLoss( const Kingdom & kingdom ) const
{
#ifndef NDEBUG
#if defined( WITH_DEBUG )
    const Player * kingdomPlayer = Players::Get( kingdom.GetColor() );
    assert( kingdomPlayer != nullptr );

    const bool isKingdomInAIAutoControlMode = kingdomPlayer->isAIAutoControlMode();
#else
    const bool isKingdomInAIAutoControlMode = false;
#endif // WITH_DEBUG
#endif // !NDEBUG

    // This method should only be called for a human-controlled kingdom
    assert( kingdom.isControlHuman() || isKingdomInAIAutoControlMode );

    const Settings & conf = Settings::Get();

    // First of all, check if the other players have fulfilled certain victory conditions yet
    const std::array<std::pair<uint32_t, uint32_t>, 3> enemyVictoryConditions
        = { std::make_pair<uint32_t, uint32_t>( GameOver::WINS_TOWN, GameOver::LOSS_ENEMY_WINS_TOWN ),
            std::make_pair<uint32_t, uint32_t>( GameOver::WINS_ARTIFACT, GameOver::LOSS_ENEMY_WINS_ARTIFACT ),
            std::make_pair<uint32_t, uint32_t>( GameOver::WINS_GOLD, GameOver::LOSS_ENEMY_WINS_GOLD ) };

    for ( const auto & [victoryCond, defeatCond] : enemyVictoryConditions ) {
        if ( conf.getCurrentMapInfo().ConditionWins() & victoryCond ) {
            const PlayerColor color = vec_kingdoms.FindWins( victoryCond );

            if ( color != PlayerColor::NONE && color != kingdom.GetColor() ) {
                return defeatCond;
            }
        }
    }

    if ( conf.isCampaignGameType() && Campaign::getCurrentScenarioLossCondition() == Campaign::ScenarioLossCondition::LOSE_ALL_SORCERESS_VILLAGES ) {
        const VecCastles & castles = kingdom.GetCastles();

        if ( std::none_of( castles.begin(), castles.end(), []( const Castle * castle ) {
                 assert( castle != nullptr );

                 return !castle->isCastle() && castle->GetRace() == Race::SORC;
             } ) ) {
            return GameOver::LOSS_ALL;
        }
    }

    const std::array<uint32_t, 4> defeatConditions = { GameOver::LOSS_ALL, GameOver::LOSS_TOWN, GameOver::LOSS_HERO, GameOver::LOSS_TIME };

    for ( const uint32_t cond : defeatConditions ) {
        if ( ( ( conf.getCurrentMapInfo().ConditionLoss() & cond ) == cond ) && KingdomIsLoss( kingdom, cond ) ) {
            return cond;
        }
    }

    return GameOver::COND_NONE;
}

uint32_t World::getDistance( const Heroes & hero, int targetIndex )
{
    _pathfinder.reEvaluateIfNeeded( hero );
    return _pathfinder.getDistance( targetIndex );
}

std::list<Route::Step> World::getPath( const Heroes & hero, int targetIndex )
{
    _pathfinder.reEvaluateIfNeeded( hero );
    return _pathfinder.buildPath( targetIndex );
}

void World::resetPathfinder()
{
    _pathfinder.reset();
    AI::Planner::Get().resetPathfinder();
}

void World::updatePassabilities()
{
    for ( Maps::Tile & tile : vec_tiles ) {
        // If tile is empty then update tile's object type if needed.
        if ( tile.getMainObjectType() == MP2::OBJ_NONE ) {
            tile.updateObjectType();
        }

        tile.setInitialPassability();
    }

    // Once the original passabilities are set we know all neighbours. Now we have to update passabilities based on neighbours.
    for ( Maps::Tile & tile : vec_tiles ) {
        tile.updatePassability();
    }
}

void World::PostLoad( const bool setTilePassabilities, const bool updateUidCounterToMaximum )
{
    if ( setTilePassabilities ) {
        updatePassabilities();
    }

    // Cache all tiles that that contain stone liths of a certain type (depending on object sprite index).
    _allTeleports.clear();

    for ( const int32_t index : Maps::GetObjectPositions( MP2::OBJ_STONE_LITHS ) ) {
        const auto * objectPart = Maps::getObjectPartByActionType( getTile( index ), MP2::OBJ_STONE_LITHS );
        if ( objectPart == nullptr ) {
            // It looks like it is a broken map. No way the tile doesn't have this object.
            assert( 0 );
            continue;
        }

        _allTeleports[objectPart->icnIndex].push_back( index );
    }

    // Cache all tiles that contain a certain part of the whirlpool (depending on object sprite index).
    _allWhirlpools.clear();

    // Whirlpools are unique objects because they can have boats on them which are leftovers from heroes
    // which disembarked on land. Tiles with boats and whirlpools are marked as Boat objects.
    // So, searching by type is not accurate as these tiles will be skipped.
    for ( const auto & [index, objectPart] : Maps::getObjectParts( MP2::OBJ_WHIRLPOOL ) ) {
        assert( objectPart != nullptr );

        _allWhirlpools[objectPart->icnIndex].push_back( index );
    }

    // Cache all positions of Eye of Magi objects.
    _allEyeOfMagi.clear();
    for ( const int32_t index : Maps::GetObjectPositions( MP2::OBJ_EYE_OF_MAGI ) ) {
        _allEyeOfMagi.emplace_back( index );
    }

    resetPathfinder();
    ComputeStaticAnalysis();

    // Find the maximum UID value.
    uint32_t maxUid = 0;

    for ( const Maps::Tile & tile : vec_tiles ) {
        maxUid = std::max( tile.getMainObjectPart()._uid, maxUid );

        for ( const auto & part : tile.getGroundObjectParts() ) {
            maxUid = std::max( part._uid, maxUid );
        }

        for ( const auto & part : tile.getTopObjectParts() ) {
            maxUid = std::max( part._uid, maxUid );
        }
    }

    if ( updateUidCounterToMaximum ) {
        // And set the UID counter value with the found maximum.
        Maps::setLastObjectUID( maxUid );
    }
    else {
        // Check that 'getNewObjectUID()' will return values that will not match the existing ones on the started map.
        assert( Maps::getLastObjectUID() >= maxUid );
    }
}

uint32_t World::GetWeekSeed() const
{
    uint32_t weekSeed = _seed;

    fheroes2::hashCombine( weekSeed, week );

    return weekSeed;
}

bool World::isAnyKingdomVisited( const MP2::MapObjectType objectType, const int32_t dstIndex ) const
{
    const PlayerColorsVector colors( Game::GetKingdomColors() );
    return std::any_of( colors.cbegin(), colors.cend(),
                        [this, objectType, dstIndex]( const PlayerColor color ) { return GetKingdom( color ).isVisited( dstIndex, objectType ); } );
}

void World::fixFrenchCharactersInStrings()
{
    for ( Heroes * hero : vec_heroes ) {
        hero->fixFrenchCharactersInName();
    }
    for ( Castle * castle : vec_castles ) {
        castle->fixFrenchCharactersInName();
    }
    for ( std::string & str : _customRumors ) {
        fheroes2::fixFrenchCharactersForMP2Map( str );
    }
    for ( EventDate & event : vec_eventsday ) {
        fheroes2::fixFrenchCharactersForMP2Map( event.message );
    }

    for ( const auto & tile : vec_tiles ) {
        switch ( tile.getMainObjectType() ) {
        case MP2::OBJ_SIGN:
        case MP2::OBJ_BOTTLE: {
            MapSign * sign = dynamic_cast<MapSign *>( map_objects.get( tile.GetIndex() ) );
            if ( sign != nullptr ) {
                fheroes2::fixFrenchCharactersForMP2Map( sign->message.text );
            }
            break;
        }
        case MP2::OBJ_EVENT: {
            MapEvent * event = dynamic_cast<MapEvent *>( map_objects.get( tile.GetIndex() ) );
            if ( event != nullptr ) {
                fheroes2::fixFrenchCharactersForMP2Map( event->message );
            }
            break;
        }
        case MP2::OBJ_SPHINX: {
            MapSphinx * sphinx = dynamic_cast<MapSphinx *>( map_objects.get( tile.GetIndex() ) );
            if ( sphinx != nullptr ) {
                for ( std::string & text : sphinx->answers ) {
                    fheroes2::fixFrenchCharactersForMP2Map( text );
                }
                fheroes2::fixFrenchCharactersForMP2Map( sphinx->riddle );
            }
            break;
        }
        default:
            break;
        }
    }
}

OStreamBase & operator<<( OStreamBase & stream, const CapturedObject & obj )
{
    return stream << obj.objCol << obj.guardians;
}

IStreamBase & operator>>( IStreamBase & stream, CapturedObject & obj )
{
    return stream >> obj.objCol >> obj.guardians;
}

OStreamBase & operator<<( OStreamBase & stream, const MapObjects & objs )
{
    const std::map<uint32_t, std::unique_ptr<MapBaseObject>> & objectsRef = objs._objects;

    stream.put32( static_cast<uint32_t>( objectsRef.size() ) );

    for ( const auto & [uid, obj] : objectsRef ) {
        assert( obj && obj->GetUID() == uid );

        if ( const auto * objPtr = dynamic_cast<const MapEvent *>( obj.get() ); objPtr != nullptr ) {
            stream << uid << MP2::OBJ_EVENT << *objPtr;

            continue;
        }

        if ( const auto * objPtr = dynamic_cast<const MapSphinx *>( obj.get() ); objPtr != nullptr ) {
            stream << uid << MP2::OBJ_SPHINX << *objPtr;

            continue;
        }

        if ( const auto * objPtr = dynamic_cast<const MapSign *>( obj.get() ); objPtr != nullptr ) {
            stream << uid << MP2::OBJ_SIGN << *objPtr;

            continue;
        }

        // Unknown object type
        assert( 0 );
    }

    return stream;
}

IStreamBase & operator>>( IStreamBase & stream, MapObjects & objs )
{
    std::map<uint32_t, std::unique_ptr<MapBaseObject>> & objectsRef = objs._objects;

    const uint32_t size = stream.get32();

    objectsRef.clear();

    for ( uint32_t i = 0; i < size; ++i ) {
        uint32_t uid{ 0 };
        MP2::MapObjectType type{ MP2::OBJ_NONE };
        stream >> uid;

        static_assert( LAST_SUPPORTED_FORMAT_VERSION < FORMAT_VERSION_PRE2_1103_RELEASE, "Remove the logic below." );
        if ( Game::GetVersionOfCurrentSaveFile() < FORMAT_VERSION_PRE2_1103_RELEASE ) {
            int temp{ MP2::OBJ_NONE };
            stream >> temp;

            type = static_cast<MP2::MapObjectType>( temp );
        }
        else {
            stream >> type;
        }

        std::unique_ptr<MapBaseObject> obj = [&stream, type]() -> std::unique_ptr<MapBaseObject> {
            switch ( type ) {
            case MP2::OBJ_EVENT: {
                auto ptr = std::make_unique<MapEvent>();
                stream >> *ptr;

                return ptr;
            }

            case MP2::OBJ_SPHINX: {
                auto ptr = std::make_unique<MapSphinx>();
                stream >> *ptr;

                return ptr;
            }

            case MP2::OBJ_SIGN: {
                auto ptr = std::make_unique<MapSign>();
                stream >> *ptr;

                return ptr;
            }

            default:
                break;
            }

            return {};
        }();

        if ( !obj ) {
            // Most likely the save file is corrupted.
            stream.setFail();

            continue;
        }

        if ( obj->GetUID() != uid ) {
            // Most likely the save file is corrupted.
            stream.setFail();

            continue;
        }

        if ( const auto [dummy, inserted] = objectsRef.try_emplace( uid, std::move( obj ) ); !inserted ) {
            // Most likely the save file is corrupted.
            stream.setFail();
        }
    }

    return stream;
}

OStreamBase & operator<<( OStreamBase & stream, const World & w )
{
    return stream << w.width << w.height << w.vec_tiles << w.vec_heroes << w.vec_castles << w.vec_kingdoms << w._customRumors << w.vec_eventsday << w.map_captureobj
                  << w.ultimate_artifact << w.day << w.week << w.month << w.heroIdAsWinCondition << w.heroIdAsLossCondition << w.map_objects << w._seed;
}

IStreamBase & operator>>( IStreamBase & stream, World & w )
{
    static_assert( LAST_SUPPORTED_FORMAT_VERSION < FORMAT_VERSION_1010_RELEASE, "Remove the logic below." );
    if ( Game::GetVersionOfCurrentSaveFile() < FORMAT_VERSION_1010_RELEASE ) {
        uint16_t width = 0;
        uint16_t height = 0;

        stream >> width >> height;
        w.width = width;
        w.height = height;
    }
    else {
        stream >> w.width >> w.height;
    }

    stream >> w.vec_tiles >> w.vec_heroes >> w.vec_castles >> w.vec_kingdoms >> w._customRumors >> w.vec_eventsday >> w.map_captureobj >> w.ultimate_artifact >> w.day
        >> w.week >> w.month >> w.heroIdAsWinCondition >> w.heroIdAsLossCondition;

    static_assert( LAST_SUPPORTED_FORMAT_VERSION < FORMAT_VERSION_1010_RELEASE, "Remove the logic below." );
    if ( Game::GetVersionOfCurrentSaveFile() < FORMAT_VERSION_1010_RELEASE ) {
        ++w.heroIdAsWinCondition;
        ++w.heroIdAsLossCondition;
    }

    static_assert( LAST_SUPPORTED_FORMAT_VERSION < FORMAT_VERSION_PPRE1_1106_RELEASE, "Remove the logic below." );
    if ( Game::GetVersionOfCurrentSaveFile() < FORMAT_VERSION_PPRE1_1106_RELEASE ) {
        // Update flags for Mine and Lighthouse captured objects.
        for ( const auto & [tileIndex, object] : w.map_captureobj ) {
            if ( object.GetColor() == PlayerColor::NONE ) {
                // This object is not owned by anyone.
                continue;
            }

            if ( object.objCol.first == MP2::OBJ_MINE ) {
                // Update Mine flag.
                // Remove old flag parts.
                const int32_t topIndex = tileIndex - w.width;
                if ( topIndex >= 0 ) {
                    // Remove top tile flag part.
                    w.vec_tiles[topIndex].removeObjects( MP2::OBJ_ICN_TYPE_FLAG32 );
                }
                if ( ( topIndex % w.width ) < ( w.width - 1 ) ) {
                    // Remove top-right tile flag part.
                    w.vec_tiles[topIndex + 1].removeObjects( MP2::OBJ_ICN_TYPE_FLAG32 );
                }

                // Set new flag.
                w.vec_tiles[tileIndex].setOwnershipFlag( MP2::OBJ_MINE, object.GetColor() );
            }
            else if ( object.objCol.first == MP2::OBJ_LIGHTHOUSE ) {
                // Update Lighthouse flag parts.
                w.vec_tiles[tileIndex].setOwnershipFlag( MP2::OBJ_LIGHTHOUSE, object.GetColor() );
            }
        }
    }

    stream >> w.map_objects >> w._seed;

    w.PostLoad( false, true );

    return stream;
}

void EventDate::LoadFromMP2( const std::vector<uint8_t> & data )
{
    assert( data.size() >= MP2::MP2_EVENT_STRUCTURE_MIN_SIZE );

    assert( data[0] == 0 );

    assert( data[42] == 1 );

    // Structure containing information about a timed global event.
    //
    // - uint8_t (1 byte)
    //     Always 0 as an indicator that this indeed a timed global object.
    //
    // - int32_t (4 bytes)
    //     The amount of Wood to be given. Can be negative.
    //
    // - int32_t (4 bytes)
    //     The amount of Mercury to be given. Can be negative.
    //
    // - int32_t (4 bytes)
    //     The amount of Ore to be given. Can be negative.
    //
    // - int32_t (4 bytes)
    //     The amount of Sulfur to be given. Can be negative.
    //
    // - int32_t (4 bytes)
    //     The amount of Crystals to be given. Can be negative.
    //
    // - int32_t (4 bytes)
    //     The amount of Gems to be given. Can be negative.
    //
    // - int32_t (4 bytes)
    //     The amount of Gold to be given. Can be negative.
    //
    // - uint16_t (2 bytes)
    //     Possible artifacts to be given. Not in use.
    //
    // - uint16_t (2 bytes)
    //     A flag whether the event is applicable for AI players as well.
    //
    // - uint16_t (2 bytes)
    //     The first day of occurrence of the event.
    //
    // - uint16_t (2 bytes)
    //     Period in days when the event repeats. 0 means that the event never repeats.
    //
    // - unused 5 bytes
    //    Always 0.
    //
    // - unused 1 byte
    //    Always 1.
    //
    // - uint8_t (1 byte)
    //     A flag to determine whether Blue player receives the event.
    //
    // - uint8_t (1 byte)
    //     A flag to determine whether Green player receives the event.
    //
    // - uint8_t (1 byte)
    //     A flag to determine whether Red player receives the event.
    //
    // - uint8_t (1 byte)
    //     A flag to determine whether Yellow player receives the event.
    //
    // - uint8_t (1 byte)
    //     A flag to determine whether Orange player receives the event.
    //
    // - uint8_t (1 byte)
    //     A flag to determine whether Purple player receives the event.
    //
    // - string
    //    Null terminated string containing the event text.

    ROStreamBuf dataStream( data );

    dataStream.skip( 1 );

    // Get the amount of resources.
    resource.wood = static_cast<int32_t>( dataStream.getLE32() );
    resource.mercury = static_cast<int32_t>( dataStream.getLE32() );
    resource.ore = static_cast<int32_t>( dataStream.getLE32() );
    resource.sulfur = static_cast<int32_t>( dataStream.getLE32() );
    resource.crystal = static_cast<int32_t>( dataStream.getLE32() );
    resource.gems = static_cast<int32_t>( dataStream.getLE32() );
    resource.gold = static_cast<int32_t>( dataStream.getLE32() );

    dataStream.skip( 2 );

    // The event applies to AI players as well.
    isApplicableForAIPlayers = ( dataStream.getLE16() != 0 );

    // Get the first day of occurrence.
    firstOccurrenceDay = dataStream.getLE16();

    // Get the repeat period.
    repeatPeriodInDays = dataStream.getLE16();

    dataStream.skip( 6 );

    colors = 0;

    if ( dataStream.get() ) {
        colors |= PlayerColor::BLUE;
    }

    if ( dataStream.get() ) {
        colors |= PlayerColor::GREEN;
    }

    if ( dataStream.get() ) {
        colors |= PlayerColor::RED;
    }

    if ( dataStream.get() ) {
        colors |= PlayerColor::YELLOW;
    }

    if ( dataStream.get() ) {
        colors |= PlayerColor::ORANGE;
    }

    if ( dataStream.get() ) {
        colors |= PlayerColor::PURPLE;
    }

    message = dataStream.getString();

    DEBUG_LOG( DBG_GAME, DBG_INFO, "A timed event which occurs at day " << firstOccurrenceDay << " contains a message: " << message )
}

bool EventDate::isAllow( const PlayerColor color, const uint32_t date ) const
{
    if ( ( colors & color ) == 0 ) {
        // This player color is not allowed for the event.
        return false;
    }

    if ( firstOccurrenceDay > date ) {
        // The date has not come.
        return false;
    }

    if ( firstOccurrenceDay == date ) {
        return true;
    }

    if ( repeatPeriodInDays == 0 ) {
        // This is not the same date and the event does not repeat.
        return false;
    }

    return ( ( date - firstOccurrenceDay ) % repeatPeriodInDays ) == 0;
}

OStreamBase & operator<<( OStreamBase & stream, const EventDate & obj )
{
    return stream << obj.resource << obj.isApplicableForAIPlayers << obj.firstOccurrenceDay << obj.repeatPeriodInDays << obj.colors << obj.message << obj.title;
}

IStreamBase & operator>>( IStreamBase & stream, EventDate & obj )
{
    stream >> obj.resource >> obj.isApplicableForAIPlayers >> obj.firstOccurrenceDay >> obj.repeatPeriodInDays;

    static_assert( LAST_SUPPORTED_FORMAT_VERSION < FORMAT_VERSION_1109_RELEASE, "Remove the logic below." );
    if ( Game::GetVersionOfCurrentSaveFile() < FORMAT_VERSION_1109_RELEASE ) {
        int temp;
        stream >> temp;
        obj.colors = static_cast<PlayerColorsSet>( temp );
    }
    else {
        stream >> obj.colors;
    }

    return stream >> obj.message >> obj.title;
}
